1. Field of the Invention
The present invention relates generally to a custom ankle brace system and a method of fabricating the same.
2. Description of the Prior Art
Individuals with certain types of foot and/or ankle conditions often suffer from limited mobility and require the use of braces or other aids for walking. These conditions often require the immobilization of the foot and/or ankle or at least partial restriction of movement of the foot in the ankle or joint area. Immobilization is accomplished through the use of braces, orthotics or other devices.
Currently, orthotic devices for the foot and ankle are custom fabricated by applying and fitting the orthotic device to a duplicate model of the affected patient's limb. The degree to which a custom device fits the patient and is comfortable to wear depends on the experience and skill level of the professional taking a cast of the affected limb, the accuracy any measurements taken and the technician who must work from the information provided to fabricate the custom device. The various methods for constructing the duplicate model of the patient's affected limb sometimes results in be inaccurately sized and shaped casts. Inaccuracies are caused by variables in casting methods, such as applying the casting bandage too loose or too tight, imprecise measurements of the affected limb and the translation of information during mold production. These uncertainties can result in a final product that is not intimate in fit and lacks comfort, stability and utility.
A second issue affecting the quality of a custom molded ankle brace is the type of materials utilized in the manufacture of the orthotic device. The materials currently used for production tend to be thick and bulky. For instance, many of the current lace or gauntlet devices use cowhide leather inner liners and/or outer layers. Authentic leather is not uniform in thickness and will therefore result in a product with inconsistent size and shape. Many of these devices are also manufactured using solvent based adhesives, such as master's cement or an equivalent.
Typically, a series of presized blank brace support units are constructed, which are intended for further customization based upon the particular patient's needs. The thermoplastics used for manufacturing the support portions of the brace are difficult to remold or reshape during this customization. The most commonly used thermoplastics in the orthotic industry require high temperatures to shape and mold. These plastics are difficult to adjust after the initial molding and cumbersome to handle due to the high temperatures required to re-soften the material so that it becomes malleable. Alternatively, low-temperature thermoplastics in use tend to become flaccid and lose their pre-molded shape when reheated. In addition, these low temperature plastics tend to become gummy and self-sticking. Thus, reworking the material to conform to a particular patient often results in a loss of rigidity and a decrease in support. Because the current plastics are not amenable to adjustment, it is also difficult to grossly adjust the device in response to a change in the patients' anatomy due to growth or swelling of the limb. Instead, only spot heating and adjustment is possible. Many patients, such as children, are forced to purchase orthotic devices frequently due to the changing size of their limbs as they age. Lastly, many prior art devices, as a result of the non-uniform materials and the strength characteristics of the thermoplastics used in production, must be constructed at a greater thickness to provide the degree of rigidity and support needed.
The device in Castro, U.S. Patent Application Publication No. 2004/0034316 and U.S. Patent Application Publication No. 2007/0203441, comprises a unitary, heat-moldable ankle and arch support system encased in leather. The device is manufactured from a flat sheet of plastic material which is molded into pre-shaped and pre-sized ankle braces. The plastic material is folded along the bottom of the foot, excluding the heel, and then upward along the ankle and leg. The back of the leg is left uncovered by the plastic so that the orthotic may be properly molded, thus decreasing the rigidity of the orthotic. In addition, the patient's heel is left unsupported by the plastic material because the bottom portion of the plastic support does not extend to entire length of the sole of the foot. The brace is covered with a material such as leather and then heated in boiling fluids before fitting over the foot of an individual. The thermoplastic material described comprises an olefinic polymer. Olefin, also known as polypropylene or polyethylene is a long-chain polymer synthetic fiber. It is produced by the polymerization of ethylene and/or propylene gases under very specific conditions. Olefinic polymers loose their rigidity and strength at the temperatures required for remolding. The olefinic material must therefore be used at a greater thickness in order to provide adequate support. Finally, the procedure of heating the orthotic in boiling water or liquid will affect any cover materials, for instance leather coverings, which in turn interfere with the fitting process.
Thus, a need exists for a custom made orthotic device that is fabricated out of thinner material without a loss in strength. Such a device would be capable of becoming malleable at a temperature low enough so the material may be custom molded on the affected limb without harming the patient. The device would keep its general shape and integrity when reheated but remain pliable enough to mold onto an affected body part. The device would insure an intimate fit, achieve a true duplication of the patient's anatomy, and provide low profile support.